Means for supporting and positioning core bars in flasks, and combinations of such means with core bars and flasks



lwrw Z, 1936. D J. R. MCWANE 2,042,907

MEANS FOR SUPPORTING AND POSITIONING CORE BARS IN FLASKS, ANDCOMBINATIONS OF SUCH MEANS WITH CORE BARS AND FLASKS Filed May 11, 19545 Sheets-Sheet l myumm mllllllililli k I I m June 2, 1936. 1R, McWANE2,042,907

MEANS FOR SUPPORTING AND POSITIONING CORE BARS IN FLASKS, ANDCOMBINATIONS OF SUCH MEANS WITH CORE BARS AND FLASKS Filed May 11, 19343 Sheets-Sheet 2' June 2, Eg J MCWANE 2,2,907

MEANS FOR SUPPORTING AND POSITIONING CORE BARS IN FLASKS, ANDCOMBINATIONS OF SUCH MEANS WITH CORE BARS AND FLASKS Filed May 11, 19543 Sheets-Sheet 3 mm mm all f z I ii.

Patented June 2, 1936 UNETED STATES PATENT OFFICE MEANS FOR SUPPORTINGAND POSITION- ING CORE BARS IN FLASKS, AND COIVIBI- NATIONS OF SUCHMEANS WITH CORE BARS AND FLASKS Application May 11, 1934, Serial No.725,198

4 Claims.

This invention relates generally to means for supporting core bars inflasks and to combinations of such means with core bars and flasks. Moreparticularly, the invention relates to means for supporting core bars inflasks in the production of pipes cast horizontally and to combinationsof such means with horizontal core bars and flasks.

For many years it was considered impractical if not commerciallyimpossible to cast pipes and similar cylindrical articles horizontally,i. e., with the axis of the mold and core disposed substantially in ahorizontal plane. This was due principally to the fact that in priorattempts to cast such articles horizontally it was considered necessaryto employ chaplets for holding the core centered with respect to themold cavity, and these chaplets, being cast into the pipe or otherarticle, resulted in the formation of leakage spaces between the stemsof the chaplets and the metal cast around the stems. Chaplets wereemployed in order to prevent deflection of the core or core bar due toseveral different forces, viz.; the weight of the core or core bar, thesubstantially lateral pressure on the core exerted by the velocitypressure of the stream of metal entering the mold, the unequal expansionof the top and bottom portions of the core bar resulting from the bottomof the bar being heated before the top thereof during filling of themold from the bottom up, and the upward vertical force due to thenatural buoyancy of the core in the molten metal.

In Patent 1,702,657 and Reissue Patents 17,121, 17,362, and 17,363, allin the name of James R. McWane, there are disclosed means for supportingcore bars in flasks for the production of horizontally cast pipe in suchmanner that the cores may be so positioned and held in the molds as toproduce, without the use of chaplets, pipes or the like having an eventhickness of metal. Many thousands of tons of pressure-tight pipe havebeen produced successfully by using the means disclosed in the patentsreferred to.

Generally stated, the core positioning means disclosed in the priorpatents are constructed and arranged to exert upon the core bars adefinite pressure capable of springing the core bars and giving them aninitial deflection from a purely centered position. The direction anddegree of the initial deflection is such that when a mold is poured theforces referred to above will just overcome the initial deflection ofthe core bar, moving the latter to centered position relative to themold cavity so that the solidified pipe or other casting will be ofuniform thickness.

Inasmuch as forces act on the core bars both horizontally and verticallyduring pouring and solidification, it is necessary that the core bars beinitially deflected both horizontally and vertically. The meansdisclosed in the prior patents referred to include pressure-producingelements which act in a direction inclined to both the horizontal andthe vertical. In cases where the initial deflection of the core bar, sayin a horizontal plane, is correct and the initial vertical deflectionnot correct, it has been found that actuation of the inclinedpressure-producing elements for correcting the initial verticaldeflection disturbs the horizontal deflection and thereby renders thecomplete initial deflection-setting of the core bar somewhat difficult.

An object of the present invention is to provide improved means forpositioning and/or supporting a core bar in a horizontal mold adapted toexert initial deflection-producing pressures in a purely horizontaldirection only. Another object is to provide a novel combination of suchmeans with a flask and core bar. Further objects are to provide novelrenewable bushings for supporting the core bars in horizontal molds, toprovide a novel three point core bar support, to provide an improvedform of yoke for association with a single core bar and having means forexerting purely downward pressure on the core bar, and to provide animproved device for exerting upward pressure on a core bar yetpermitting the latter to expand and contract longitudinally withoutundue binding. Other objects will become apparent from a reading of thefollowing description, the appended claims, and the accompanyingdrawings, in which:

Figure 1 is a top plan view of drag or bottom mold flask, core barstherein, and means arranged in accordance with the invention forpositioning and supporting the core bars;

Figure 2 is a view in end elevation of the flask and associated partsshown in Figure 1, looking from the bell or left hand end as viewed inFigure 1;

Figure 3 is a sectional view taken on the line 33 of Figure 1;

Figure 4 is a fragmentary view in vertical section showing a replaceablecore bar bushing support;

Figure 5 is a top plan view of the replaceable bushing;

Figure 6 is a top plan view similar to Figure 1 but showing the copeflask section in position on the drag;

Figure 7 is a view in end elevation looking from the left of Figure 6;

Figure 8 is a sectional view on the line 88 of Figure 7;

Figure 9 is a fragmentary top plan view showing modified mold supportingand positioning means;

Figure 10 is a sectional view on the line lG-l0 of Figure 9; 1

Figure 11 is a view in end elevation of the flask section and associatedparts shown in Figure 9;

Figure 12 is a View in side elevation of a yoke; and

Figure 13 is a perspective view of a core bar supporting block.

The invention is capable of embodiment in a number of different formsbut for the purpose of illustration there is shown in the drawings ahorizontally disposed mold flask A having drag and cope sections l and 2respectively and core bars B, B coated with core sand and positioned inthe flask as shown clearly in Figure l. The coated c-ore bars and thesand mold within the flask conjointly define mold cavities C and Crespectively, these cavities including bell ends 3-3 and spigot endsll-4', respectively. The drag flask section i (see particularly Figures1, 2-, and 3) comprises longitudinally extending sides connected by anend wall 5 adjacent the bell end of the mold and an end wall (5 adjacentthe spigot end thereof. Plates i and 8 extend across the drag flasksection in planes spaced inward from the end walls 5 and 6.

The end wall 5 is formed with semicircular openings 9 and ii, the endwall 6 is provided with two similar openings m, 50', the plate 1 isformed with two semicircular openings H, H, and the plate 8 is formedwith two similar openings I2 and E2. The openings 9, Ill, H, and i2 arein line with the axis of the mold cavity C and are somewhat greater indiameter than the core bar B which extends through these openings.Similarly the openings 9, Ni, ii and i2 are in line with the axis of themold cavity C and are of somewhat greater diameter than the core bar Cwhich extends through these openings.

. For supportingand positioning the core bar B in the flask there areprovided primary supporting means preferably comprising a replaceablesemicircular bushing I3 positioned in the opening H in the plate I and asemicircular bushing l4 positioned in the opening I2 in the plate 8, theinner surfaces of these bushings serving as seats for receiving the belland spigot ends of the core bar B. The bushings may be secured in theflask by any suitable means but preferably by some means permitting themto be removed and replaced easily. Suitable means are shown in Figure 4as comprising flat headed screws l5 extending through openings in thebushings and having threaded engagement with the flask, the heads of thescrews being disposed in counter sunk portions of the bushing. It hasbeen found that the primary core bar supports sometimes become worn sothat the core bar will not be accurately centered when placed in theflask. By providing replaceable bushings such as are described above, itis, possible to correct any uncentered condition of the core bar easilyby merely removing a worn bushing and substituting another which hasbeen machined or ground on its inner surface in a manner to' produce theshifting of the core bar necessary to efiect substantially perfectcentering thereof in the mold. The cost of maintaining the core barscentered in this manner has been found to be considerably less than whenfollowing the old practice of remachining the flask itself or evenproviding a new plate 1 or 8.

For positioning the core bar longitudinally with respect to the mold,the bell end of the core bar may be provided with a circumferentialflange it the inner surface of which is adapted to abut against a lug ITon the end wall 5 of the drag flask section. The lug I? is of suchlength and the flange leis so located on the core bar that when the twoare in abutting relation as shown in Figure 1 the core will have theproper position longitudinally with respect to the mold.

It will be understood that the primary supports provided by the bushingsl3 and IG do not in themselves serve to effect any initial deflection ofthe core bar which, as stated above, is necessary in order to compensatefor the deflection which occurs during pouring and solidification of themetal. For effecting the necessary initial lateral deflection of thecore bar means movable in a purely horizontal direction and preferablysubstantially in the plane of the flask joint and into engagement withthe core bar on opposite sides thereof are provided. In the illustratedembodimerit of the invention this means includes a screw it extendingthrough and having threaded connection with the lug H and a screw l9having threaded connection with a lug 2E3, these screws being located onopposite sides of the core bar B and lying in a horizontal planesubstantially in the plane of the flask joint.

When preparing the mold and core assembly for pouring, the screws l8 and19 are manipulated in a manner to effect deflection of the core bar inthe direction necessary to compensate for the lateral pressure exertedby the molten metal entering the mold. For example, if the metal entersthe mold cavity C from a point between the cavity C and the cavity C, itwill be necessary in preparing the mold and core assembly to initiallydeflect the core bar B inwardly with respect to the center of the dragflask section or in other words downwardly as viewed in Figure 1. Thisdeflection may be accomplished by turning the screw l8 in a direction tocause it to travel inwardly against the core bar B and by turning thescrew 19 in a direction to cause it to move away from the core bar. Ifthe metal is introduced into the mold cavity on the opposite sidethereof, the operation of the screws will be reversed, i. e., the screwl9 will be caused to exert pressure on the core bar and the screw i8 55eifected, operation of the screws !8 and is to produce the desiredinitial lateral deflection will not disturb the already correct initialvertical deflection.

The means for effecting the necessary initial vertical deflection of thecore bar B are separate from the means described above for efiecting thelateral deflection and in the form shown in Fig ures 1 to 8, inclusiveinclude a lug 2| projecting outwardly from the end wall 5 of the drag, ascrew 22 extending vertically through the lug and engaging the bottom ofthe core bar, a lug 23 extending outwardly from the end wall 6 of thedrag and screw 24 extending vertically through the lug 23 and engagingthe bottom of the core bar. A bar- 25 extends longitudinally andcentrally of the dragv section between the end wall 5 and the plate 7and provides an anchorage for a vertically extending .bolt 26 whichpasses through a yoke 21 extending over and engaging the tops of thecore bars B and B, a nut 28 having threaded connection with the boltadapted to engage the top of the yoke 21 for forcing the latterdownwardly to exert pressure upon the tops of the core bars B and B.There is further provided a bar 29 extending between the plate 8 and theend wall 6 of the flask and forming an anchorage for a verticallyextending bolt 36 which passes up through a yoke 3| extending across andengaging the tops of the core bars B and B, a nut 32 having threadedconnection with the bolt 30 and being adapted to exert pressure upon theyoke 3i for causing the latter in turn to press down on the core bars.It will be apparent that by manipulating the screws 22 and 24 and thenuts 28 and 32 the desired initial vertical deflection of the core bar Bmay be produced.

These means provide for deflecting the bar either upwardly or downwardlyfrom its initial position. Usually it is necessary to deflect the bardownwardly but in some cases the weight of the bar itself together withthe sand on the bar causes too great an initial downward deflection andthe bar has to be deflected upwardly.

The means for supporting, positioning and effecting initial deflectionof the core bar B are the same as those for supporting, positioning andinitially deflecting the core bar B and therefore will not be describedin detail. For convenience, however, the positioning and initialdeflection producing parts associated with the core bar B are designatedby the same reference characters as corresponding parts associated withthe core bar B, with the exception that those associated with the corebar B are primed. Thus the lug 2i and screw 22 extending therethroughand engaging the bottom of the core bar B' are the same respectively asthe lug 2| and the screw 22 passing therethrough for engagement with thebottom of the core bar B, and so on.

A modified form of supporting, positioning and initial deflectionproducing means is shown in Figures 9 to 13, inclusive. In themodification the primary supporting means includes a stationary pad 33which may be integral with the plate 1 and located under and arranged toengage with the body of the core bar B and side set screws 34 and 35having threaded connec tion respectively with lugs 36 and 31 on the dragflask section, these screws being located on opposite sides of the corebar B and preferably lying substantially in the plane of the flaskjoint. An appreciable amount of clearance is provided between the corebar and the opening H in the plate I of the drag so that the pad 33 andthe screws 34 and 35 together constitute a three point. primary supportfor the core bar. Wear on the pad. 33 or the core bar may be correctedor compensated for by grinding the pad or by building the pad up bywelding and then grinding. Wear on the sides of the core bar or heads ofthe screws 34 and 35 can be compensated for by adjusting the positionsof the screws in their associated lugs. Thus the three point support maybe maintained in proper condition or adjustment more economically thanwould be the case if the plate 1 supported the core bar B directly sincein the latter case in order to compensate for wear it would be necessaryeither to replace the plate or build up the entire inner surface of theopening l l and then remachine the latter.

In the modification shown in Figures 9 to 13, inclusive, the initiallateral deflection producing screws l8 and I9 are the same as thosedescribed in connection with the form shown in Figures 1 to 8, but forexerting pressure on the bottom of the core bar there is provided ascrew 38 having threaded connection with the lug 39 on the drag flaskand having its head facing upwardly under the core bar, and a block 40interposed between the head of the screw and the bottom of the core bar.In the form shown this block is formed on its lower surface with aspherically shaped recess 4| adapted to fit over the rounded head of thescrew 38 so as to permit relative turning movement between the screw andthe block. Preferably the upper face of the block 49 is provided withtwo parallel raised portions or pads 4242 whose surfaces conform to thecylindrical outer surface of the core bar, these surfaces being adaptedto engage the bottom of the core bar. The amount of force necessary tobe exerted upon the bottom of the core bar for producing the requiredinitial vertical deflection thereof may be produced by turning the screw38 in the lug 39. The block 40 will remain stationary relative to thecore bar during such turning of the screw so that wearing of the corebar will be prevented. The pads 42-42 on the block 40 provide anextended seat for the core bar which permits longitudinal expansion ofthe latter when it is heated during pouring of the mold.

Figures 9 to 12 also disclose a modified form of yoke 43 which differsfrom the yokes 21 and 3| shown in Figure 1 essentially in that the yoke43 is adapted to cooperate with only one core bar whereas the yokes 21and 3! shown in Figure 1 necessarily cooperate with two core bars. Inusing the form of yoke shown in Figure 1 it is not possible to changethe downward pressure acting on one core bar without changing thedownward pressure acting on the other so that in practice thisarrangement sometimes makes it somewhat difficult to obtain the desiredinitial vertical deflection of both core bars. The yoke 43, however, isadapted for cooperation with the flask and a single core bar only so asto avoid this difficulty. In the illustrated embodiment of themodification the yoke is of generally inverted U-shape and is arrangedto span the associated core bar B, the legs of the yoke being providedwith hook shaped feet 44 and 45 adapted to engage under fixed parts 46and 41 of the flask. A screw 43 passes through and has threadedconnection with the portion of the hook intermediate its legs and isadapted, when turned in the proper direction, to exert force downwardlyupon the core bar. It will be understood that the initial verticaldeflection of the core bar may be produced by manipulation of the screws48 and 38 in a manner similar to the method of producing the initialvertical deflection of the core bar by means of the screws 22 and 24 andthe nuts 28 and 32 shown in Figure 1.

The embodiments shown herein by way of illustration have been found tobe practical and are the at present preferred forms of the invention,but it will be understood that various changes may be made in thespecific construction and relative arrangement of the parts withoutdeparting from the invention as defined in the claims.

What is claimed is:

1. In combination, a flask; a core bar therein;

iii)

a yoke spanning the core bar and having legs disposed on opposite sidesof the core bar; means on said legs separately and operatively engagingrelatively fixed flask parts on opposite sides of said core bar; andmeans having connection with the portion of the yoke between said legsand adapted to exert a clamping pressure on said core bar.

2. In combination, a flask; a core bar therein; a yoke spanning the corebar and having legs disposed on opposite sides of the core bar; hookedfeet on said legs engaging under relatively fixed flask parts; and meanshaving connection with the portion of the yoke between said legs andadapted to exert a clamping pressure on said core bar.

3. Means for positioning a horizontal core bar in a horizontal flaskcomprising screw means engaging the core bar and being mounted on avertical axis and being movable in a purely vertical direction forexerting only vertical pressure on the core barj and other screw meansengaging the core bar and being mounted on a horizontal axis and beingmovable in a purely horizontal direction for exerting pressure on thecore bar in a horizontal direction only.

4. Means for supporting a core bar in a flask, the flask having asemi-circular opening for accommodating said core bar, said meanscomprising primary supporting means including a pad integral or fixedwith respect to the flask and being located at the bottom of saidsemi-circular opening and being of relatively small circumferentialextent as compared to the extent of said semi-circular opening; and sidesupporting elements on opposite sides of the core bar above said pad,said pad and said side supporting elements thereby providing athree-point support.

ARTHUR T. MCWANE, WILLIAM McWANE, JELKS H. CABAN'ISS, Executors of theEstate of James R. McWane,

Deceased.

